32 research outputs found
Judging a video by its bitstream cover
Classifying videos into distinct categories, such as Sport and Music Video,
is crucial for multimedia understanding and retrieval, especially in an age
where an immense volume of video content is constantly being generated.
Traditional methods require video decompression to extract pixel-level features
like color, texture, and motion, thereby increasing computational and storage
demands. Moreover, these methods often suffer from performance degradation in
low-quality videos. We present a novel approach that examines only the
post-compression bitstream of a video to perform classification, eliminating
the need for bitstream. We validate our approach using a custom-built data set
comprising over 29,000 YouTube video clips, totaling 6,000 hours and spanning
11 distinct categories. Our preliminary evaluations indicate precision,
accuracy, and recall rates well over 80%. The algorithm operates approximately
15,000 times faster than real-time for 30fps videos, outperforming traditional
Dynamic Time Warping (DTW) algorithm by six orders of magnitude
Leveraging Compressed Frame Sizes For Ultra-Fast Video Classification
Classifying videos into distinct categories, such as Sport and Music Video,
is crucial for multimedia understanding and retrieval, especially when an
immense volume of video content is being constantly generated. Traditional
methods require video decompression to extract pixel-level features like color,
texture, and motion, thereby increasing computational and storage demands.
Moreover, these methods often suffer from performance degradation in
low-quality videos. We present a novel approach that examines only the
post-compression bitstream of a video to perform classification, eliminating
the need for bitstream decoding. To validate our approach, we built a
comprehensive data set comprising over 29,000 YouTube video clips, totaling
6,000 hours and spanning 11 distinct categories. Our evaluations indicate
precision, accuracy, and recall rates consistently above 80%, many exceeding
90%, and some reaching 99%. The algorithm operates approximately 15,000 times
faster than real-time for 30fps videos, outperforming traditional Dynamic Time
Warping (DTW) algorithm by seven orders of magnitude.Comment: 5 pages, 5 figures, 1 table. arXiv admin note: substantial text
overlap with arXiv:2309.0736
Modification Method of Tooth Profile of Locomotive Traction Gear Based on Rodent Arm Variation
Locomotive traction gear is the key component to power transmission and speed control in locomotive transmission system, which plays an important role in locomotive running speed and load-carrying torque. Considering that there is not universal rule for the method of modification of locomotive gear at present, in this paper, the tooth profile modification is considered with the combination of the increased contact ratio and the variation of the moment arm of action. Based on the principle of modification, according to the load direction after modification, the change rule of moment arm of action after modification is determined, and the interval range of tooth profile modification is also determined. Taking a certain locomotive traction gear as an example, the results obtained through the method of modification which based on combining moment arm of action variation with the increase of contact ratio and the method based on the traditional empirical formula are compared through finite element simulation respectively, on this account to verify the superiority of the theory of modification, which has important theoretical significance for profile modification of locomotive traction gear
"I Prefer an Everyday Style and Dislike Big Food Fighters": Integrating Foodshow into Everyday Life
In this paper, we examine a genre of User Generated Videos (UGV) centering around food which we term "foodshow". While Korean mukbang features streamers eat large quantities of food, foodshow features mundane activities in life. Toward understanding unique watching practices of foodshow given its difference from mukbang, we interviewed 12 foodshow viewers in China, uncovering active and life-oriented watching of foodshow - viewers actively choose and watch foodshow which walks a fine line between authenticity and attractiveness, reflecting everyday existence and involving moderate performance at the same time. With these unique features, foodshow watching is integrated into viewers' daily life, and helps in eating, sleeping, and emotional adjustment, in addition to entertainment. Based on the findings, we suggest design implications for healthier and more beneficial foodshow.Ope
Evolution of zinc oxide nanostructures through kinetics control †
In-depth understanding of the kinetics of the vapor deposition process is substantial for advancing this capable bottom-up nanostructure synthesis approach into a versatile large-scale nanomanufacturing technology. In this paper, we report a systematic study of the vapor deposition kinetics of ZnO nanomaterials under controlled atmosphere and properly refined deposition conditions. The experiments clearly evidenced the self-catalyzed growth of ZnO NWs via the formation of ZnO nanoflowers. This result illustrated how ZnO morphologies were associated with the discrepancy between oxidation rate and condensation rate of Zn. The capability of switching the NW morphologies and possibly mechanisms was demonstrated by kinetically controlling the deposition system. The high Zn composition during the deposition resulted in strongly luminescent NWs, which can be used for optical imaging applications. This research discovered a fundamental kinetics that governs the mechanisms and morphology selection of nanostructures in a non-catalyst growth system
Effect and Mechanism of Armillaria mellea 07-22 Fermentation on the Degradation of Zearalenone
This study used Armillaria mellea 07-22 as the experimental strain to degrade zearalenone (ZEN) by fungal biological fermentation. The degradation effects of Armillaria mellea on ZEN were studied, including the degradation effects of different concentrations of ZEN by the strain and the effects of different culture time, culture temperature, initial pH value and inoculation amount on the degradation of ZEN by the strain. Then the degradation mechanism was explored, the degradation effects of mycelium, fermentation supernatant and cell contents on ZEN were analyzed, and the effects of different fermentation time, pH values, and metal ions on degradation of ZEN by fermentation supernatant were studied, and the correlation between degradation effect and laccase production activity of the strain was illustrated. The results showed that Armillaria mellea 07-22 had a good degradation effect on ZEN. When the ZEN concentration was 5 μg/mL, the optimal degradation conditions were culture time of 8 days, culture temperature of 27 ℃, initial pH of 7.0, and inoculation amount of 10%. At this time, the degradation rate of ZEN was 78.72%. The degradation rates of ZEN by mycelium, fermentation supernatant and cell contents were 47.42%, 37.05% and 13.08% respectively. The extracellular enzymes secreted by Am-07-22 were the main way to degrade ZEN, and the mycelium cells also had a certain adsorption effect on ZEN. In addition, the correlation between the degradation rate of ZEN by fermentation supernatant and laccase activity was 0.973, and Cu2+ had the best promoting effect on the degradation of ZEN by fermentation supernatant
Exome sequencing in fetuses with short long bones detected by ultrasonography: A retrospective cohort study
Background: Prenatal diagnosis of fetal short long bones (SLBs) was reported to be associated with skeletal dysplasias, chromosomal abnormalities, and genetic syndromes. This study aims to identify the genetic causes for fetal short long bones, and retrospectively evaluate the additional diagnostic yield of exome sequencing (ES) for short long bones following the use of conventional genetic testing.Methods: A cohort of ninety-four fetuses with sonographically identified short long bones was analyzed by trio-exome sequencing between January 2016 and June 2021. Fetuses with abnormal results of karyotype or chromosomal microarray analysis were excluded. Variants were interpreted based on ACMG/AMP guidelines. All diagnostic de novo variants were validated by Sanger sequencing.Results: Of the 94 fetuses, 38 (40.4%) were found to carry causal genetic variants (pathogenic or likely pathogenic) in sixteen genes with 38 variants. Five fetuses (5.3%) had variant(s) of uncertain significance. Thirty-five cases (37.2%) were diagnosed as genetic skeletal dysplasias including 14 different diseases that were classified into 10 groups according to the Nosology and Classification of Genetic Skeletal Disorders. The most common disease in the cohort was achondroplasia (28.9%), followed by osteogenesis imperfecta (18.4%), thanatophoric dysplasia (10.5%), chondrogenesis (7.9%), and 3-M syndrome (5.3%). The diagnostic yield in fetuses with isolated short long bones was lower than the fetuses with non-isolated short long bones, but not reached statistical significance (27.3% vs. 44.4%; p = 0.151). Whereas, the rate in the fetuses with other skeletal abnormalities was significantly higher than those with non-skeletal abnormalities (59.4% vs. 32.5%, p = 0.023), and the diagnostic rate was significantly higher in femur length (FL) below -4SDs group compared with FL 2-4SDs below GA group (72.5% vs. 16.7%; p < 0.001). A long-term follow-up showed that outcomes for fetuses with FL 2-4SDs below GA were significantly better than those with FL below -4SDs. Additionally, fourteen (36.8%) novel short long bones-related variants were identified in the present study.Conclusion: The findings suggest that in fetuses with short long bones routine genetic tests failed to determine the underlying causes, exome sequencing could add clinically relevant information that could assist the clinical management of pregnancies. Novel pathogenic variants identified may broaden the mutation spectrum for the disorders and contributes to clinical consultation and subsequent pregnancy examination
Single-Cell RNA Sequencing of Peripheral Blood Mononuclear Cells From Acute Myocardial Infarction
BackgroundAcute myocardial infarction (AMI) can occur in patients with atherosclerotic disease, with or without plaque rupture. Previous studies have indicated a set of immune responses to plaque rupture. However, the specific circulating immune cell subsets that mediate inflammatory plaque rupture remain elusive.MethodsTen AMI patients were enrolled in our study (five with and five without plaque rupture; plaque characteristics were identified by optical coherence tomography). By single-cell RNA sequencing, we analyzed the transcriptomic profile of peripheral blood mononuclear cells.ResultsWe identified 27 cell clusters among 82,550 cells, including monocytes, T cells, NK cells, B cells, megakaryocytes, and CD34+ cells. Classical and non-classical monocytes constitute the major inflammatory cell types, and pro-inflammatory genes such as CCL5, TLR7, and CX3CR1 were significantly upregulated in patients with plaque rupture, while the neutrophil activation and degranulation genes FPR2, MMP9, and CLEC4D were significantly expressed in the intermediate monocytes derived from patients without plaque rupture. We also found that CD4+ effector T cells may contribute to plaque rupture by producing a range of cytokines and inflammatory-related chemokines, while CD8+ effector T cells express more effector molecules in patients without plaque rupture, such as GZMB, GNLY, and PRF1, which may contribute to the progress of plaque erosion. Additionally, NK and B cells played a significant role in activating inflammatory cells and promoting chemokine production in the plaque rupture. Cell–cell communication elaborated characteristics in signaling pathways dominated by inflammatory activation of classical monocytes in patients with plaque rupture.ConclusionsOur studies demonstrate that the circulating immune cells of patients with plaque rupture exhibit highly pro-inflammatory characteristics, while plaque erosion is mainly associated with intermediate monocyte amplification, neutrophil activation, and degranulation. These findings may provide novel targets for the precise treatment of patients with AMI